Long considered an adults-only condition, blood pressure high enough to be called hypertension is affecting a much younger audience.

A member of that audience is Olivia, a delightful 13-year old girl that enjoys life outdoors in her British Columbia neighbourhood. Her recent hypertension diagnosis surprised Olivia’s mother, Rebecca: “It’s common to think of hypertension as an older person’s concern.”

Indeed, it’s a common categorization. Even an online search for “hypertension patient” yields images almost exclusively of salt-and-pepper-haired adults. And it isn’t necessarily wrong: over 7.5 million Canadians – one in four adults – has hypertension, the leading global risk for death and disability. The complications to which uncontrolled hypertension can lead are conditions also labelled for older adults, like congestive heart failure, stroke, atrial fibrillation, renal disease, and coronary heart disease. What’s missed is that hypertension now affects our children; one in fifty Canadians under the age of 18.

The prevalence of hypertension in Canadian children is closely associated with childhood obesity and sedentary activity patterns in youth. Elevated blood pressure in childhood tracks to adulthood, leading to those serious complications mentioned. Because children with hypertension may already display evidence of target organ damage, prompt identification and treatment is critical. But until recently, primary care practitioners had few, if any, resources to guide them.

For nearly two decades, Hypertension Canada has produced clinical practice guidelines for hypertension in adults based on a wealth of available, solid evidence. Paediatric literature, however, is inherently limited by small numbers of participants, fewer trials, and a long latency to the development of vascular outcomes. The void was a challenge for kids like Olivia and the primary care practitioners who care for them.

“I was lucky,” says Rebecca, “I had terrific support to help get the diagnosis and to manage the condition, but that’s not everyone’s experience.”

Paediatric guidelines genesis

The increasing prevalence of hypertension in children and the lack of guidance for its management motivated the Hypertension Canada Guidelines Committee in 2013 to establish a subgroup comprising hypertension specialists in paediatric cardiology, paediatric nephrology and nursing in to address the void.

Over the next two years, following the highly structured Hypertension Canada Guidelines process, the expert paediatric subgroup systematically evaluated existing literature to create recommendations. In 2015, their draft recommendations passed the rigorous review of the Guidelines Committee’s 75 members, and the first guidelines for blood pressure measurement, diagnosis, and investigation of paediatric hypertension were published in 2016.  The next crucial step was to develop management guidance and the 2017 Guidelines for the Diagnosis, Assessment, Prevention, and Treatment of Paediatric Hypertension were published this May in The Canadian Journal of Cardiology.

General principles

The guidelines aim to help primary care practitioners and paediatricians to identify, investigate, and manage hypertension in children and adolescents and to recommend when referral to experts in paediatric hypertension is appropriate. While the 10 guidelines consider specifics of age, sex, height, BMI and others, and are meant to be thoughtfully applied appropriate to the patient and with clinical judgement, some general principles are more broadly applicable.

• Measure blood pressure regularly in children three years of age and older.

While there are practical challenges to accurately measure blood pressure in infants and very young children, regularly measure those three years of age and older for early identification of hypertension.

• Accurate measurement of blood pressure is foundational to treatment.

Blood pressure should be measured using standardized paediatric techniques [a standardized approach is included in the guidelines] using a mercury sphygmomanometer, aneroid sphygmomanometer, or oscillometric device. Abnormal oscillometric values should be confirmed with auscultation.

• Identification of hypertension as primary or secondary in children is critical.

In children less than five years of age, primary hypertension is uncommon, and secondary causes – such as renal, renovascular, endocrine and cardiac disorders – need to be aggressively sought to guide therapy and follow up. Conversely, in obese children and adolescents, primary hypertension is more common than secondary.

Prevention and treatment

The paediatric and adult guidelines share in common the importance of health behaviour modification. The strongest effect on blood pressure in obese children and adolescents was BMI. With reported associations between childhood blood pressure, diet, and physical activity, studies to modify these risk factors have shown some improvements in markers of cardiovascular health. Evidence for dietary improvements is increasing, showing positive changes with salt reduction and increased potassium found in fruits, vegetables and dairy products. The Dietary Approaches to Stop Hypertension (DASH) diet, which is high in fruits, vegetables, grains, and low fat dairy; and is low in fat, sugar, and sodium, has shown benefits in both adults and children.

The combination of dietary improvements as well as physical activity seem to amplify the beneficial effects. While most schools teach healthy eating and physical activity, children with hypertension, obesity, or those at risk for either might benefit from specific advice from primary care practitioners to improve these healthy behaviours.

Future focus

The 2017 guidelines stress that health behaviour modification lies at the foundation, given the noted association of obesity in children and sedentary patterns in youth with hypertension prevalence in children. Fortunately, there are encouraging data suggesting that the prevalence of obesity is stabilizing and that, at least among overweight or obese adolescents in the United States, blood pressure in children is decreasing.

“These findings underscore the importance of a continued evidence based approach toward improving the cardiovascular health of Canadian children,” notes Anne Fournier, paediatric subgroup chair, and paediatric cardiologist at the University of Montréal. “The timing of these guidelines is opportune.”

Given the relative newness of these guidelines, and the complexities necessary to consider in treating children, there is much work ahead to help primary care practitioners with their implementation. As a standard practice with Hypertension Canada Guidelines, diagnostic and therapeutic algorithm tools will be developed, and the guidelines will be annually reviewed to capture new evidence as it becomes available.

“We’re committed to continual improvement,” says Nadia Khan, president of Hypertension Canada and professor of medicine at the University of British Columbia agrees. “Our goal is to ensure healthcare professionals are aware of the increased prevalence of hypertension in children and that our guidelines can help them in their treatment decisions to prevent the serious and deadly complications that can emerge much later.”

Rebecca is happy to know that new guidelines are now in place to help support children like her daughter, Olivia. “By having guidelines in place, it will help those kids that are being missed.”

Angelique Berg is the Chief Executive Officer at Hypertension Canada.

The 2017 Hypertension Canada Guidelines can only be realized with your participation. Here are some things you can do:

• Check out the full paediatric Guidelines
• Download the adult Guidelines at guidelines.hypertension.ca.
• View the educational resources and videos available at hypertension.ca.
• Attend a Hypertension Canada Primary Care Education session near you or online, or the annual Canadian Hypertension Congress.
• Become a member of Hypertension Canada for continued updates.

Hypertension Canada is the only national non-profit organization dedicated solely to the prevention and control of hypertension and its complications. Powered by a professional volunteer network of hypertension experts, Hypertension Canada develops and produces the nation’s clinical practice guidelines for the prevention, diagnosis and treatment of hypertension. Created by professionals, for professionals, Hypertension Canada’s tools and educational resources help to keep healthcare professionals at the leading edge in hypertension diagnosis and care.